Abstract : A number of analytic techniques used in Artificial Intelligence are examined in the context of decision making in mine countermeasures. Attention is directed at five major techniques, involving statistical inference, probabilistic inference, evidential reasoning, fuzzy logic and artificial neural networks. In the cases of statistical inference and evidential reasoning, solutions to appropriate problems are described. Eleven other techniques are dealt with more briefly, in most cases with worked examples of appropriate naval application. The main conclusion reached is that, in view of the probable shortage of accurate information under operational conditions, evidential reasoning and fuzzy logic are likely to be the most appropriate means for presenting relevant data to decision makers, and that artificial neural networks will be useful for representing complicated or empirical relationships between observed factors.